Question: Which is the capital of the twinned administrative body of Sofia?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q472 wdt:P190 ?obj . ?obj wdt:P31 wd:Q5119 } 
Answer: Warsaw, Skopje, Moscow, Tbilisi, Prague, Athens, Helsinki, Bratislava, Kyiv, Yerevan, Madrid, Algiers, Ankara, Amman, Bucharest, Tirana, Berlin, London, Brussels